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wolvo
11-09-2010, 14:02
Hey all i know very little about turbo chargers i was looking for a little advice, im looking to upgrade to a bigger turbo than my std unit and id like to know what my options are ?
Ive heard a t3 hybrid is a good idea as they spin up quick, ive also heard about vnt turbo's (no idea what they are) but ive been in a car with one fitted and it fecking flew :D. So anyone who could advise which way to go id appreciate it and also any ideas on prices and suppliers so i can get the money together....id gather buying of ebay is a bad idea lol

JRP
11-09-2010, 14:47
Back to basics.. what changes have you made to your engine from stock?

On a stock/o.e engine full t25 would blow your socks off, a T3 would be ultra laggy on std internals..

Its all dependant

JRP
11-09-2010, 14:50
You must also be looking at intercooler set up, also fueling.. and making sure all forms of cooling are up to the crack..

unfortunatly its not a case of bigger turbo more boost.. people doing that is where the un reliable myth sprouts its wings from.

So making sure

A. fueling
B. cooling

C. engine internals (dependant on turbo size)

assuming all these are good/ spot on you can size accordingly:cool:

JRP
11-09-2010, 14:56
Also have a flick through some of the articals in the different sections via this link..

They may help you understand some things that your not so clear on

http://www.rtoc.org/boards/forumdisplay.php?f=17 :agree:

dangerous dave
11-09-2010, 15:25
i myself would avoid the vnt, if you look at the 1/4 mile leader board the top spots are mostly t28's of some sort.. perhaps the vnt will spin up quicker but when i weight up the cost of the whole kit and add the hassle people have had setting up, its t28 for me..

i have 2 t28's to choose from, both different but although my 5 will make me poop myself on the uk roads, i wont have a fun playful car.. i had the t28 on before i took the car apart and could do journey after journey without coming onto boost, cars in the way, traffic lights, buses:cry:

i will always end up going back to a smaller turbo, t2/t25 or a full t25 with as little lag as possible..

think about what you want from your car:)

bye_all_c_ya
11-09-2010, 22:34
ive gone from t25 to vnt and must say spool up and punch on the vnt is way better then i had with the t25 but still setting the vnt up where the t25 is as good as bolt on ! :)

James5
11-09-2010, 23:11
ive gone from t25 to vnt and must say spool up and punch on the vnt is way better then i had with the t25 but still setting the vnt up where the t25 is as good as bolt on ! :)


Personal I love the VNT, had a few different turbo's over the years of 5 ownership from standard T2's through to T28's and as bye_all_c_ya advices the way the VNT comes in is just awesome once you have finished setting it up that is:D:p yes takes a little time but once setup properly it can boost like a T2 yet the power of a T3:agree: and to me there is no other option. But that's my view, I am so glad I got the VNT back in my 5 :burnrubber:

BluntyR5GTT
12-09-2010, 07:23
something iv been wondering about is i know people go for either a t25 or t28 but the later is a bit of a lag monster and the t25 sometimes aint enough for people, is there any turbo that is specced in between a t25 and t28 as surely that would be the perfect compromise :)

GTphil
12-09-2010, 10:19
Wasn't there a t28 about with a machined out t2 rear housing to reduce lag?

wolvo
12-09-2010, 10:27
I should have put a bit more info reading posts lol, i run an alloy intercooler and its fueled for 16psi at the moment (i have no problems stripping carb to mod for extra fueling if needed) internals are standard although i will fit a cam when engine has to come out, it has usual high flow air filter and big exhaust with a larger elbow also (thanks again ian) car runs at a nice temprature although all cooling is standard at the mo.
Im not looking for a 1/4 mile killer i just want to improve the amount of boost to make driving round roads more exciting so i pressume i dont want anything too big so its not gonna be to laggy.

BluntyR5GTT
12-09-2010, 10:29
sounds like a t25 is right up ur street then fella :agree:

wolvo
12-09-2010, 10:32
will any 25 bolt straight on ?, if so wheres the best place to pick one up from and what sort of price would i expect to pay bud ?

BluntyR5GTT
12-09-2010, 10:37
no any t25 wont just bolt straight on m8, there a few places to get them from adaml off here does them iirc i got quoted about £500 for a full hybrid t25 with 360 bearing etc etc, also turbo technics and aet turbos do them

BluntyR5GTT
12-09-2010, 10:38
you can also get 200sx s13 or rover tomcat t25 turbos to fit but they need modding and also aint good for anything over 16psi tbh

wolvo
12-09-2010, 13:16
do all t25 turbo's run at 16psi max or only certain types ?....im getting confused now (not hard to confuse me lol)

Markey Mark (BD)
12-09-2010, 15:10
The reason some turbo's don't like big boost is because of the bearings inside, they won't last long as there designed to do small boost for long periods.

There are a hell of alot of spec's you can have in the T25 bracket, firstly you got to decide what sort of boost you want to run and also what you want to use the car for.
From reading what you mentioned if your just want a slight upgrade how about going for a T2/T25, keep the turbine same which will keep lag to minimum and increase the compressor side to cope with the increase in boost and work effectively.

Markey Mark (BD)
12-09-2010, 15:12
something iv been wondering about is i know people go for either a t25 or t28 but the later is a bit of a lag monster and the t25 sometimes aint enough for people, is there any turbo that is specced in between a t25 and t28 as surely that would be the perfect compromise :)

T28's aren't always lag monsters, it all depends on what size turbine wheel and housing you use.
I've had one built before but using a T2 housing on the back (larger than the standard .35 though), spun up very well and quickly too.

BluntyR5GTT
12-09-2010, 23:12
on the hybrid t25/t2 i have here it has a rare .63 t2 housing on it i wonder if that would work well on the t28,
i like the sound of a t28 that aint a lag monster. when were you starting to make and hitting full boost ?

dangerous dave
12-09-2010, 23:25
on the hybrid t25/t2 i have here it has a rare .63 t2 housing on it i wonder if that would work well on the t28,
i like the sound of a t28 that aint a lag monster. when were you starting to make and hitting full boost ?

the .63 housing is what i have on my turbo with a big old t3 front, its off turbo teds old 12 odd second 5 so can produce the power if the rest of the engine etc can.. im interested to see what the lags like but wont know for a while as the cars spread over my garage floor and many rooms in the house:crap:

BluntyR5GTT
12-09-2010, 23:34
lol sounds like that could make for a lively turbo, i might look into getting this rear housing put onto a t28, what work is needed to get it fit ?

Markey Mark (BD)
13-09-2010, 15:30
lol sounds like that could make for a lively turbo, i might look into getting this rear housing put onto a t28, what work is needed to get it fit ?

The rear housing will need machining out to match the turbine wheel.
The size of the turbine wheel will make a difference too, what size/trim wheel you got in that turbo?

BluntyR5GTT
13-09-2010, 15:49
i aint got a t28 mark, i was going to go for a full t25 but im having my head turned by this t28 with t2 rear :), iv got that knackered hybrid t25/t2 here with the .63 t2 rear

Markey Mark (BD)
13-09-2010, 16:13
i aint got a t28 mark, i was going to go for a full t25 but im having my head turned by this t28 with t2 rear :), iv got that knackered hybrid t25/t2 here with the .63 t2 rear

Ah i see thats cool. ;)

I had a turbo made few years ago that had a combination of T3 housings, T25 core and wheels and T2 housings, if this sounds interesting to you i'll see if i can remember the spec.
It worked really well, was quite suprised how quick it spooled, i did increase the rear end though from the original spec due to the power tailing off abit early.

BluntyR5GTT
13-09-2010, 16:43
yeah mate that sounds ok by me :)

i was set on a full t25 but if i can get something that has a tad more punch and around the same lag as the t25 then why not eh :agree:

dangerous dave
13-09-2010, 16:58
heres my lag special sat next to turbo teds old turbo, from what the old advert said its a .42 front, .63 rear with a t34 wheel machined.. im not sure if thats what young mark here had..

the big fecker next to it is T25 0.64 A/R back end, with a T25 core, GT28RS 62 trim comp wheel and 0.60 A/R GT28 comp housing..

i know the larger turbos laggy but on a standard internal engine @18psi i thought it was ok, on my new engine im yet to test it but am sure it'll be a hell of a lot better.. as i said before the i've not tried the turbo ted but hope theres less lag and more than enough power.. i'll man up and run over 20psi on either once the cars run in again:smokin:

if your like me numbers mean nothing without a pic to go with them..
http://www.rtoc.org/boards/picture.php?albumid=150&pictureid=13067
http://www.rtoc.org/boards/picture.php?albumid=150&pictureid=13068
http://www.rtoc.org/boards/picture.php?albumid=150&pictureid=13069

Markey Mark (BD)
13-09-2010, 17:03
No Dave i had a slightly different turbo which was basically a T25 core and turbine wheel (can't remember the trim) with a T2 .47 housing machined to go over it and a cosworth T3 front compressor wheel and housing on the front.

Worked well enough on my mates old Raider which is what i got the turbo for, good enough for 12 sec runs. :D

Brigsy
13-09-2010, 17:18
That big blower would be ideal for my van Dave, let me know if you fancy parting with it;)